Highly diastereo- and enantioselective 1,6-addition of 1,3-ketoamides to -quinone methides (-QMs) using chiral NHCs as Brønsted base catalysts is developed. The reaction is based on the utilization of a 1,3-ketoamide having acidic N-H that forms a chiral ion-pair consisting of the enolate and the azolium ion. Different β-ketoamides and functionalized -QMs are applicable to the reaction. Synthetic application of the method is demonstrated the preparation of highly enantioenriched β and γ-lactam derivatives.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6144034 | PMC |
| http://dx.doi.org/10.1039/c8sc02138d | DOI Listing |
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